Just hanging on. Kelp Crabs love Orange Sea Pens. Sea Pens are filter feeders and once the current picks up the sea pen will push its way out of the sand and extend its body to catch food as it passes by in the current. The crabs then move into position, climbing up the extended sea pen and delicately picking out morsels of food.
This may seem like the crab is cheating and stealing from the sea pen however the crab acts a defender for its dining buddy. Sea pens are the favourite food of Striped Nudibranchs and the crabs will chase off any would be predators of the sea pen to protect its dinner catcher.
Thanks for reading.
Scott
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